In a small bowl, stir together cheese, chives, sour cream, mayonnaise and horseradish. Cover and refrigerate.
Preheat oven to 425°F (220°C). In a small bowl, combine garlic, rosemary, 1 tsp (5 mL) of the oil, the pepper and salt; rub all over beef, pressing to adhere.
In a large cast iron or other large ovenproof skillet, heat remaining 2 tsp (10 mL) oil over medium-high heat; brown beef all over, about 6 minutes. Transfer beef in skillet to oven and roast for about 30 minutes or until meat thermometer inserted in centre of beef reaches 145°F (63°C) for medium-rare. Transfer beef to cutting board; loosely tent with foil and let stand for 10 minutes.
Meanwhile, return skillet with cooking juices to stovetop; add wine and bring to boil over high heat, using wooden spoon to scrape up any brown bits. Boil until reduced by half, about 1 minute. Transfer jus to gravy boat, straining, if desired.
Carve beef into ¾-inch (4 cm) slices; arrange on platter. Serve with jus and Blue Cheese Horseradish Sauce.
Per each of 8 servings: 207 calories, 25 g protein, 10 g fat (4 g saturated fat), 1 g carbohydrates, 0 g fibre, 61 mg cholesterol, 292 mg sodium